Field of the Invention
The invention relates to an operative insert having processing means for processing foodstuffs in a processing device and to a device for processing foodstuffs having such an operative insert.
Discussion of Related Art
The prior art discloses rotors for manually operated devices for processing foodstuffs which bear various processing means for example for cutting, peeling, blending or tossing fruit, vegetables and herbs. Some of these devices, provided with special processing means, can also be used for kneading dough, for mixing sauces or for whipping cream. These devices are usually driven by means of crank drives, cord pull drives, toggle lever drives or humming top drives.
U.S. Pat. No. 5,156,084A discloses a manually operated food processor, which comprises a working container with a central support axle, a cover having a hand-crank drive and a number of various exchangeable rotors with processing means. In addition to a draining basket to drain salad, a cutting rotor having a plurality of radially fastened cutting knives and a mixing rotor having likewise radially arranged stirring blades are proposed. The various rotors are each pushed onto a central bearing journal in the working container and, when the cover is pushed onto the working container, are detachably connected to the crank drive in the cover by way of a positively locking tool interface. The rotational movement of the crank is transmitted via a step-up transmission to a central drive shaft, which is pushed through the base of the cover and is provided at the bottom end with a connecting pin having an external square. Depending on the desired foodstuffs processing, the rotors can be exchanged very quickly and easily. As a result of the proposed crank drive, the rotational movements are transmitted to the rotor with step-up, such that the rotational speed of the rotor is significantly higher than the rotational speed of the crank. The direct connection makes it possible for the rotor which is used in each case to be rotated optionally in various directions depending on the direction of rotation of the crank. Such changes in direction of rotation are particularly desirable when stirring or emulsifying sauces or when tossing salad or herbs. When the cutting rotor is used, the cutting knives have to be provided with a cutting edge on both sides in order to prevent blocking in the event of a change in direction of rotation. The bent knife position has additionally proved to be unfavourable, however, for operation in both directions of rotation.
The simple design, the low production costs and the mains-independent operation make such manually operated food processors popular kitchen devices, not only in emerging countries, but also in industrial countries.
In order to make it easier to cut fruit and vegetables, in particular at the start of the cutting operation, WO11157511A proposes an operative insert for devices which process foodstuffs. These devices comprise a bowl and a receptacle for the operative insert which is driven in rotation about an axis of rotation. This rotating operative insert is formed in such a manner that foodstuffs located in the bowl can be processed and/or handled, wherein the operative insert has a support body, which can be connected or is connected to the receptacle, and at least one tool, which is mounted on the support body and is movable as a result by the processing and/or handling, and which is displaceable counter to the force of a resetting means from a position of rest into a working position.
The apparatus for cutting foodstuffs which is known from US 2009/0090254 A1 eliminates the disadvantage of previously known apparatuses that, in the case of said apparatuses, a relatively large initial torque has to be applied, particularly in the case of hard foodstuffs, for instance in the form of onions or potatoes, in order to break the large, hard pieces up into smaller pieces which are easier to process. In order to avoid this, pivotable knives are arranged on the central rotor shaft, and, depending on the torque generated as a reaction to the externally applied drive torque, can be moved from a position of rest into a working position in a manner pivotable by a limited pivot angle. In the case of the applicant's known apparatus, which is marketed extremely successfully under the trade name SWIZZZPROZZZ®, two or more knives are arranged one above another, can be pivoted relative to one another and are driven about the common axis of rotation. In the position of rest, the knives are congruent one above another in an angular position. At least one of the knives is, however, mounted pivotably on the drive shaft, such that, as a consequence of the initial torque, this knife can initially yield, until it has reached a stop at which it is then likewise driven in rotation. In this way, the torque applied at the start of the processing can be lowered, since not all of the knives immediately engage with the material to be cut with a cutting action.
A disadvantage of the known apparatus, however, is that—as already noted in WO11157511A—the angle by which the knives are mounted in a freely pivotable manner is limited and relatively small.
WO10150263 A2 discloses inserts for food processors which can be used for chopping, mixing, stirring, beating and juicing. A central shaft can be connected to a drive motor by means of a spindle arranged at a first end. The second, opposite end of the central shaft is mounted in a receiving container. Radially protruding blades are fastened to the shaft in a lower region and additional processing tools can be arranged detachably in an upper region. When processing the foodstuffs, the additional processing tools are coupled fixedly to the central shaft. In certain embodiments, the central shaft is provided with a helical groove, in which corresponding cams of the additional processing tools engage and are moved into a locking position upon rotation of the central shaft in a downwards movement.